Vapour retarders / Guides

Vapor retarder latex primer instead of polyethylene sheet
Air and vapour barriers

Replacing polyethylene vapour barriers with latex paint vapor control

...Vapour retarder latex primers: Firstly, the classification of a material as either an impermeable ‘vapour barrier’ or a semi-permeable ‘vapour retarder’ is determined by how much water vapour passes through the material under specific conditions. There are vapour retarder primers on the market that exceed the requi...

Tyvek home wrap left exposed to wind and UV rays
Air and vapour barriers

Choosing the right house wrap / weather barrier, which is best?

...Vapour impermeable 0.1 perms or less Vapour semi-impermeable 1.0 perm or less and greater than 0.1 perms Vapour semi-permeable 10 perms or less and greater than 1.0 perms Vapour permeable Greater than 10 perms Understanding vapour permeability: All we are talking about so far a...

Choosing between OSB or Plywood for house sheathing for Roofs, Walls & Floors.
Wood and organic materials

Which is better, OSB or Plywood for Roofs, Walls & Floors?

...vapour permeable sheathing membrane. This risk may dictate the use of insulation products with high vapour permeability and low water retention, such as mineral fibre." Where to put vapour barriers (CMHC): "Materials that act as vapour barriers (vapour retarders), including certain types of insulation, must be loca...

Poly vapour barriers in air conditioned houses can cause mold and rot
Healthy indoor air quality

Why you should Never Install Air-Con in a Home with a Vapor Barrier

Vapor Barrier + Air-Con = Damp Moldy Walls So here's a little known fact that most HVAC installers won't tell a potential new client for central air; Polyethylene vapor barriers in combination with air conditioning in homes can rot walls because of the condensation they may cause. This is why if you have a newer hom...

Finished basements can lead to mold and mildew
Healthy indoor air quality

Why are basements moldy? How to fix or Prevent a Moldy Basement

...vapour barrier (60ng and under). At that level of moisture permeability, an almost immeasurably small amount of moisture will be able to migrate into the wall, but with no interior vapour barrier it will pass through harmlessly. EPS, XPS and mineral wool are unharmed by moisture, and perhaps most importantly, EPS and...